Evaluation of loss of heterozygosity and microsatellite instability in human pterygium: clinical correlations.

AIMS: To evaluate the incidence of loss of heterozygosity (LOH) and microsatellite instability (MI) in pterygia and their possible correlation with clinical variables. METHODS: 50 pterygia, blood, and conjunctival specimens were obtained. A personal and family history was recorded for each patient. Amplification of 15 microsatellite markers at regions 17p, 17q, 13q, 9p, and 9q was performed using the polymerase chain reaction. The electrophoretic pattern of DNA from pterygia was compared with the respective pattern from blood and conjunctiva. RESULTS: LOH incidence was the highest at 9p (48%), followed by 17q (42%). Only three cases displayed MI. LOH incidence at individual markers was positively correlated with recurrence (D9S59, p = 0.11 and D9S270, p = 0.16), family history of neoplasia (D13S175, p = 0.09), altitude of present residence (D9S112, p = 0.1), duration of the existence of pterygium (D9S144, p = 0.06), and inversely correlated with age (D9S59, p = 0.09). Concerning chromosome arms, LOH was positively correlated with the altitude of present residence (13q and 17p, p = 0.03) and duration of the existence of pterygium (13q and 17p, p = 0.09). CONCLUSIONS: LOH is a common event whereas MI is a very uncommon one at the examined markers in pterygium, indicating the presence of putative tumour suppressor genes implicated in the aetiopathogenesis of the disease. The fact that LOH at 9q31-33 was more frequent in recurrent pterygia and also correlated with known risk factors such as young age and high altitude of residence, implies a possible predictive value of this finding for postoperative recurrence.

Microsatellite instability and loss of heterozygosity in human pterygia.

AIMS/BACKGROUND: Pterygium is a common benign lesion of the corneoconjunctival limbus. Although environmental factors, such as ultraviolet irradiation, have been suggested as the main causative factor in the development of the disease, however, the aetiopathology of pterygium remains obscure. In this study the possibility of detecting genetic alterations in the microsatellite DNA of the pterygium was investigated. METHODS: Fifteen specimens were assessed for for loss of heterozygosity (LOH) and microsatellite instability (MI) by seven microsatellite markers on four chromosomal arms. RESULTS: Nine (60%) pterygia exhibited genetic alterations. Eight specimens (53%) exhibited LOH, while two specimens (13%) MI in at least one marker. 17q11.2-q21 is a commonly deleted region, as the frequency of LOH at this region is significantly high (47%). CONCLUSION: This finding indicates the existence of tumour suppressor genes in this region implicated in the disease without excluding the presence of other tumour suppressor genes in the other chromosomal regions that were examined. MI was apparent in only a few specimens but it is indeed a detectable phenomenon, suggesting that decreased fidelity in DNA replication and repair may be associated with the development of pterygium. Detection of LOH and MI, two events taking place in tumour cells or in premalignant cells, constitutes strong evidence that there must be transformed cells in the pterygial tissue and it should be considered to be a neoplastic benign lesion.

The presence of herpesviruses in pterygium.

Pterygium is a chronic disease of unknown origin and pathogenesis. It is a vision threatening disease where surgical excision is effective. We examined surgically excised symptomatic pterygia for the presence of herpesviruses such as cytomegalovirus (CMV), herpes simplex virus (HSV) and Epstein-Barr virus (EBV) DNA using the polymerase chain reaction (PCR) technique. Samples of normal conjuctival tissue from limpus at 12 or 6 hours were excised in some of the eyes treated; they were used as controls. HSV DNA was detected in 9 and CMV DNA in 8 out of the 20 examined samples. In 3 out of the 20 examined samples both HSV and CMV DNA were detected whereas EBV DNA was not found in any of the examined samples. These results suggest that HSV and CMV may contribute to the pathogenesis of pterygium.

Detection of hsv, CMV and ebv by the polymerase chain-reaction technique in patients with inflammatory eye-diseases.

Herpes simplex virus (HSV), cytomegalovirus (CMV) and Epstein-Barr virus (EBV) have been recognized as pathogenic agents of intraocular inflammatory conditions. The ability of the Polymerase Chain Reaction (PCR) technique to amplify HSV, CMV and EBV DNA from aqueous specimens makes this technique a valuable diagnostic tool for the detection of these viral pathogens in patients with ophthalmic lesions. We used PCR for the amplification of a 476 bp long sequence from the pol I gene of HSV genome, a 435 bp region of the immediate early-1 (IE-1) gene of CMV and a 375 bp sequence from the EcoRI B fragment of EBV genome. We examined 22 aqueous humour specimens from patients with uveitis and retinitis, inflammatory eye diseases, diagnosed clinically. We found HSV in 4 (18.2%), CMV in 6 (27.3%) and EBV in 1 (4.5%) out of the 22 examined patients. None of the 22 examined samples was found to be infected with more than one of the examined viral pathogens. These data confirm the implications of the members of Herpesvirus family in inflammatory inner eye diseases and the importance of PCR technique as a diagnostic tool in clinical virology.

Multifocal Best's disease and sickle cell trait.

Ophthalmoscopy performed during a routine eye checkup on a 22-year-old black man revealed multiple intraretinal, cyst-like lesions scattered throughout the macular and extramacular areas in both eyes. Based on clinical findings, morphologic appearance, and an abnormal electro--oculogram, the diagnosis of multifocal Best's macular dystrophy was made. Hemoglobin electrophoresis showed an AS pattern confirming the presence of sickle cell trait. This is the first case of the coexistence of these two genetically transmitted diseases, Best's disease and sickle cell trait.

Planning surgery in Duane's syndrome.

We present 14 patients with Duane's syndrome and discuss our experience in the surgical management of this condition applying a method that takes into account the abnormal neural mechanism involved.

[Adjustable-suture technique for the operation of strabismus (author's transl)]. / Correction précise du strabisme par des sutures ajustables.

An adjustable-suture technique for the operation of strabismus is described. The indications of the procedure and its advantage are discussed.

Visual development in successfully treated cases of congenital glaucoma.

The authors assessed visual functions in 10 children after operations for congenital glaucoma. All the children had had one or more operations previously and it was found that the visual development of the child was affected.

[Osteitis deformans cranio-orbitalis (Paget's) in a young patient. Operation and clinico-pathology study (author's transl)]. / Eine deformierende kranioorbitale Ostitis (Paget bei einer jungen Patientin (Operation und klinisch-pathologische Studien).

Among the cranio-facial anomalies involving the orbit, Paget's disease is of particular interest due to its progressive evolution and clinico-pathological characteristics. In this article a case of Paget's disease (juvenile type) with orbital expansion in a young woman of 27 years is presented. The onset of clinical symptoms were recorded at the age of 15 years progressing to optic atrophy and blindness in one eye and visual deterioration on the other. The peculiarity of this case lies on the early onset of clinical symptoms due to elective in volvement of the skull and sparing of the facial bones. The surgical decompression (removal of the roof of the orbit and upper wall of the stenosed optic canal) was successful in controlling the evolution to optic nerve atrophy in the seeing eye.